Can I update this iPad to a iOS 13

It depends on your iPad model. Identify it using this support article:--> Identify your iPad model - Apple Support

Then see this list of compatibility for the latest iPadOS version (lacking of recently released iPad 8th generation and iPad Air 4th generation):

Regards

Giulio

If your iPad has been stuck on iOS 10.3.3, then you have an over 8-year old, 2012 iPad 4th generation.

These old 8 and 9-year old iPads have not been supported by Apple in 3-4 years.

Third party iOS app developers stopped supporting their apps on these 8 and 9-year old iOS devices over 2 years, ago.

There are virtually no more third party iOS apps available for initial download from the Apple iOS App Store any longer.

Simply put, your iPad model is too old, now.

Sorry.

If you need/want an iPad with an up to date iPadOS with access to current, updated apps, then you really need to seriously consider a new iPad model OR a much, MUCH “newer” , used iPad model capable of running the latest iPadOS versions.

There are plenty of newer, older iPad models that can run the latest, current versions of iPadOS.

Sorry & Best of Luck to You!

If your iPad is currently running, or cannot be updated beyond iOS 10.3.3/4, then have an iPad4.

Update support for iPad4 ended September 2017. The final iOS releases for this model were iOS 10.3.3 (WiFi Only models) and iOS 10.3.4 (WiFi & Cellular). iPad4 cannot be updated to any later major version of iOS as it lacks the minimum hardware requirements needed to run more recent versions. The 32-bit platform upon which the iPad4 is based is effectively obsolete.

Many App Developers have also dropped support for older devices and iOS versions preceding iOS11/12/13 - and have withdrawn older versions of their Apps from the Apple App Store. Withdrawal of Apps supporting older models of iPad is making their utility and usefulness significantly more limited. Once compatible versions Apps are withdrawn, you’ll not be able (re)download or (re)install them.

If Apps that you need to use now have higher minimum iOS-version requirements, your only option is to replace your iPad with newer model. Of current models, even the entry-level iPad8 supports current iPadOS 14 - and has hardware specifications and capabilities that vastly outperform your old iPad4.

I hope this information is helpful - if only in clearly stating the limitations of your iPad4 and your available options.